you won't be doing much riding through the woods in socal. The jetstream rarely bring snow storms down that far, so expect fake snow and ice...heavy traffic, crowds, etc. You will be hanging out in the park all day...because that's basically all those resorts are. The one thing they do have is sun.

mammoth, on the other hand, is one of the best resorts on earth. Tons of real snow, frequent knee deep+ pow days, kick ass/wide open glades, everything. Haven't been there in a while, but wouldn't be surprised if they get rid of the snow guns entirely early december.